Carrying excessive weight using backpacks has been recognized as a major cause of back pain among children and adults. Backpacks are popular among school children and adults because they arc easy to use and do not require one's hands for operation. However, there are health concerns arising from the repetitive use of back packs when loads in excess of 10–15% of one's body weight are carried on the back for extended period. Wheeled bags have been designed in an attempt to relieve the back and shoulders from bearing most of the weight. However, existing wheeled bag designs have some disadvantages.
Wheeled backpacks and wheeled bags are not as popular as traditional backpacks and bags for a number of reasons, such as: (i) they are operated by hand and therefore appear as being impractical; (ii) they need to be supported and controlled actively by one hand to maintain balance; (iii) a significant part of the weight is born by the arm which may be stressed after extended operation; and (iv) pulling a wheeled device by hand while walking interferes with correct body posture and may also induce stress on the shoulder and spine.